This invention relates to the field of supporting assemblies to hold concrete form structures in place to pour concrete floors for bridges and the like, and particularly to the adjustability feature thereof to obtain proper depth for the concrete floor when poured and uniformity of such depth through the entire span of the floor.
The typical form structures for pouring concrete floors for bridges, high rise buildings and the like, comprise ledgers extending laterally between the bridge beams or floor beams, stringers extending longitudinally across and on top of the ledgers, and plywood sheets on top of the stringers to provide the floor on which the concrete is to be poured. The ledgers are supported by hanger bolts hanging down from hanger bars laying laterally across the upper surface of the bridge beams or floor beams, having support plates at the lower ends of the hanger bolts bearing against threaded nuts and with end portions of the ledgers resting on the support plates.
The problem with prior art support assemblies is that the depth of the plywood flooring cannot be adjusted from above after the plywood has been laid on the stringers. In order to reach the threaded nuts at the lower ends of the hanger bolts to rotate and thereby raise or lower each ledger and the portion of plywood flooring supported thereby, it is necessary for workmen to do so from below. However, since the plywood flooring is in place, communication with workmen above who can measure the flooring depth relative to the upper surface of the bridge beams or floor beams is difficult if not a practical impossibility.
If workmen try to reach the adjusting nuts below from above the plywood flooring, such as by removing one panel and trying to reach down below, there is the danger that the workmen will slip and fall, that he will drop his wrench which may hit someone below the bridge, and any adjustment made by this awkward procedure is not likely to be as accurate and precise as if the adjustment can be made from above.
The support assembly in accordance with the present invention solves that problem by providing depth adjustable hanger bolt assemblies which can be adjusted as to depth of the plywood floor of the concrete form from above the plywood flooring after it has been put in place, and such depth can be made uniform throughout the entire surface area of the floor. Furthermore, the hanger bolt assemblies can be utilized after the concrete floor has hardened to lower the form structure enough to be removed from the hardened concrete safely in a piece by piece maneuver while the support assembly is still in place to prevent any individual pieces from falling accidentally and hitting someone below.
Prior art devices in this field known to the inventor include those set forth in the following United States patents.
U.S. Pat. No. 3,989,219 which discloses an elevation gauge to measure depth of concrete to be laid, and a prior art support assembly in which the nut supporting the plate on which the ledger rests is welded to the plate so it cannot be rotated independently of the plate.
Others examined by the inventor in an attempt to determine whether his invention was sufficiently different are:
In Class 411/84:
U.S. Pat. No. 4,830,203; 4,789,286; 4,750,310; 4,722,647; 4,708,554; 4,671,580; 4,661,006; 4,645,393; 4,629,381; 4,600,226; 4,529,244; 4,486,133; 4,239,139; 4,227,722; 4,070,847; 4,021,129; 4,015,390; 3,873,224; 3,846,851; 3,813,179; 3,599,693; 3,483,910; 3,456,706; 3,329,601; 3,322,177; 3,309,119; 3,288,512; 3,186,049; 3,150,703; 3,117,610; 3,037,731; and 2,542,375;
In Class 411/85:
U.S. Pat. No. 4,840,525; 4,830,531; 4,828,440; 4,790,701; 4,784,554; 4,784,552; 4,768,907; 4,758,124; 4,741,582; 4,695,212; 4,666,355; 4,661,030; 4,661,006; 4,630,982; 4,623,182; 4,571,135; 4,545,697; 4,488,844 and 3,446,261;
In Class 411/88:
U.S. Pat. No. 4,836,043; 4,740,124; 4,475,857; 4,329,097; 2,879,092;
In Class 411/90:
U.S. Pat. No. 4,852,700; 4,740,124; 4,562,707; and 3,623,761;
In Class 411/102:
U.S. Pat. No. 4,767,371; 4,329,097; 4,219,386; and 3,351,116;
In Class 411/116:
U.S. Pat. No. 4,789,286; 4,767,371; 4,661,030; 4,637,641; 4,618,272; 4,377,360; 4,341,053; 4,325,178; 4,283,091; 4,263,952; 4,210,372; 4,191,235; 4,183,387; 4,113,227; 4,106,541; 4,074,491; 4,046,481; 4,017,946; 3,890,758; 3,880,535; 3,874,624; 3,825,283; 3,804,140; 3,734,459; 3,694,013; 3,636,241; 3,620,574; 3,606,393; 3,504,723; 3,498,655; 3,493,201; 3,478,802; 3,434,261; 3,424,064; 3,403,605; 3,378,288; 3,377,633; 3,367,383; and 3,357,730;
In Class 411/102:
U.S. Pat. No. 4,767,371; 4,329,097; 4,219,386; 3,351,116; 2,372,772; 1,812,319; 1,448,605; 1,413,976; 1,200,285; 1,039,483; 944,666; 887,382; 870,547; 846,949; 729,966; 594,950; 530,290; 431,705; 365,674; 190,443 and 128,815;
In Class 411/83:
U.S. Pat. No. 4,754,749; 4,613,265; 4,570,303; 4,312,145; 4,283,091; 4,274,460; 4,257,466; 4,257,465; 4,252,167; 4,236,562; 4,185,937; 4,150,618; 4,138,198; 4,124,974; 4,121,700; 4,113,921; 4,113,227; 4,106,541; 4,087,201; 4,061,400; 3,920,338; 3,870,092; 3,863,300; 3,797,548; 3,677,588; 3,511,289; 3,458,132; 3,399,269; 3,393,724; 3,390,500; 3,363,280; 3,329,875; 3,308,587; 3,285,312; 3,218,101; 3,175,795; 3,164,323; 3,111,704; 3,031,220; 3,016,077; 2,955,291; 2,940,712; 2,883,720; 2,842,384; 2,832,390; 2,799,900; 2,795,261; 2,773,620; 2,771,642; 2,768,037; 3,743,143; 2,741,290; 2,737,993; 2,731,791; 2,720,392; 2,692,518; 2,672,659; 2,670,513; 2,651,488; 2,649,126; 2,635,923; 2,634,940; 2,544,387;
In Class 411/84:
U.S. Pat. No. 4,830,203; 4,789,286; 4,750,310; 4,722,647; 4,708,554; 4,671,580; 4,661,006; 4,645,393; 4,629,381; 4,600,226; 4,529,244; 4,486,133; 4,239,139; 4,227,722; 4,070,847; 4,021,129; 4,015,390; 3,873,224; 3,846,851; 3,813,179; 3,599,693; 3,483,910; 3,456,706; 3,429,601; 3,322,177; 3,309,119; 3,288,512; 3,186,049; 3,150,703; 3,117,610; 2,542,375.